50 TRANSACTIONS OF THE WAGNER FREE 



stamiiicuni), attached to the under surfaces of the lettuce bonnets, or to 

 their roots, which also supported numbers of diminutive leeches, and 

 two or more forms of crustaceans, one of them a species of Pandalus. 

 The shells were in nearly all cases very thin, and translucent. 



FAUNA OF LAKE OKEECHOBEE. All our observations tend to belief 

 that the fauna of the lake is a very deficient one, and that it is distinctly 

 uniform for the greater part of its extent. We dragged at intervals 

 all along our traverse, with the result of bringing to the surface scarcely 

 more than a half dozen species of animals. Indeed, if we Jeave out 

 of account the immediate border line of the lake, the entire catch 

 consisted almost exclusively of two species or varieties of Paludina 

 (P. Georgiana, P. liiicata), and two or three species of Unio (U. Bucklcyi, 

 U. amygdalwn). These mollusks, together with a minute Bythinella-like 

 gasteropod of uncertain relationship, were exceedingly abundant in the 

 lake just off the mouth of the canal, and the dredge came up laden 

 with their shells. Only a comparative few of the shells were without 

 the animals, and in such cases they were largely water-worn, and decal- 

 cified. A large proportion of the living Unios had their umbones eroded. 

 Out toward Observation Island the mollusks became much less numerous, 

 but on the north of the lake, between the mouth of the Kissimmee River 

 and Taylor's Creek, they again became plentiful, especially along the 

 beach line of the latter water, where the shells, in company with those of 

 Venus cancellata, already mentioned, were thrown up in considerable 

 abundance. They were also fairly plentiful in the vegetable muck of 

 Eagle Bay. The remaining species of Mollusca observed in the lake 

 were the forms to which reference has already been made as occurring 

 on the shore of Observation Island, and on the leaves and roots of the 

 lettuce-bonnets of both Taylor's Creek and Eagle Bay. They are 

 Liiiinca cohtmella, Planorbis Icntus, Pliysa gyrina, and Splucrinin staini/ici/ni. 

 Off Observation Island I scooped up a rock made up essentially of minute 

 Bythinellae (?), but whether this was of an absolutely recent formation,- 

 or a fragment derived from some hidden fossiliferous deposit, I was 

 unable to determine with positiveness.* The species of shell contained 

 in the rock was identical with that dredged up in association with the 

 Unios and Paludinas. 



A large proportion of the hauls brought up considerable numbers of 

 a fresh-water shrimp of the genus Pandalus, identical with the species 



* The affinities of the little gasteropod are doubtful. The surface of the shell is 

 distinctly costulated, and to this extent different from that of any species of the genus with 

 which I am acquainted. Ober mentions a minutely fossiliferous rock occurring toward the 

 southern border of the lake, which is not unlikely structurally identical with the fragment 

 above mentioned. 



